Add following filter on a column in SAP HANA Analytical view using if statement
if(Col1='a') col2=Col2
else if(Col2='b') col2=col2*1
Can someone help to give me syntax for HANA IF statement for following logic?
Why not using the documentation at the first place?
Not really clear what you are trying to do here. Look's like you are calculating something using col2 based on comparison on col1. As View will not allow you to update the value in the column, you will need to create col3 and put there the following:
if("Col1" = 'a',"Col2", if("Col1" = 'b',"Col2" * 1,'not a not b') )
BTW, do you think col2=col2*1 makes any sense?
Is it possible that you (or Shidai) are confusing the IF-Function with the IF-Statement? Both are working differently:
SELECT IF("Col1"=='a', 'aaahhh', 'uhhhhh') FROM DUMMY;
This works just like in an Excel: If Col1 is 'a' then the first value is returned, otherwise the second.
DECLARE x VARCHAR(100);
IF "Col1"='a'
THEN
x := "Col2";
ELSEIF "Col2"='b'
THEN
x := "Col2" * 1;
END IF
This is a control structure and only allowed in a SQLScript block, e.g. a stored procedure or anonymous block. You cannot use it in a simple SELECT statement.
It's not so clear what you are trying to do with assigning to col2, so I used x instead.
Also note:
HANA is case-sensitive. If you want to use the column Col1 you must write "Col1".
There is also CASE, which works similar to the IF-Function.
Related
TLDR; Is there anything I can set in an Oracle Form that would let me bind a placeholder to a Data Block's ORDER BY Clause?
I'm developing a form using Oracle Form Builder 10.1.2.3.0 (because it's interfacing with a system that makes other form types undesirable).
It has a Data Block with Query Data Source Type = Table.
Its WHERE Clause allows the user to be flexible in the search, producing rows of varying interest. I want rows with a perfect match to appear before those that are not.
To implement this specification, I wrote the form's WHERE Clause and ORDER BY Clause to reflect this SQL*Plus example:
var sf varchar2(30)
exec :sf := 'X'
with mdual as (
select case when level=1 then dummy else dummy || level end dummy
from dual
connect by level <= 2
)
select *
from mdual
where :sf is null or dummy like '%' || upper(:sf) || '%'
order by case when :sf = dummy then 0 else 1 end asc, dummy;
The form variable reference is not as simple as :sf and the WHERE Clause is a bit more complicated as is the ORDER BY Clause but this type of query is valid. When executed in SQL*Plus, it produces exactly the type of result I desire. You can reverse the first sort expression to prove it.
When I execute the form, I get an ORA-1008 until I comment the first ORDER BY expression.
My conclusion is that Oracle Forms binds placeholder references in a WHERE Clause but not an ORDER BY Clause.
I could experiment with setting the Query Data Source Type to Procedure and pass the procedure the filter field but a view has more utility than a procedure and so I'd prefer to keep using the view that I've defined for the Query Data Source Type.
Is there a way I can coerce Oracle Forms to do what I consider the right thing?
You can use SET_BLOCK_PROPERTY built-in function in order to make it dynamical and depending on a local or bind variable such as
DECLARE
v_orderby := ' CASE WHEN '||:sf||' = ''dummy'' THEN 0 ELSE 1 END, dummy';
BEGIN
SET_BLOCK_PROPERTY('block1',ORDER_BY, v_orderby);
EXECUTE_QUERY;
END;
which might be invoked from a trigger such as WHEN-NEW-BLOCK-INSTANCE after sending cursor to this block by using another action such as clicking on a button or pressing a key such as enter etc.
I know the right syntax for having a function definition in the WITH clause. I know the right syntax for having a subquery in the WITH clause. But I have been unable to find an example of having a subquery and a function definition in the WITH clause of a SELECT statement.
If I have:
with totals as ( select colum_name from some_table )
select sum(column_name) from totals;
How do I add a function definition in the WITH clause?
Since you can't find much/anything about this from Oracle, I don't think it is a good idea to use it. Anyway, this works in 18.1:
WITH
FUNCTION with_plus(p IN NUMBER) RETURN NUMBER IS
BEGIN
RETURN p + 1;
END;
FUNCTION with_min(p IN NUMBER) RETURN NUMBER IS
BEGIN
RETURN p - 1;
END;
qry1 AS (
SELECT with_plus(10) plus
FROM DUAL
),
qry2 AS (
SELECT plus, with_min(10) min
FROM qry1
)
SELECT *
FROM qry2
;
/
So don't forget the slash / at the end.
If you ever find out how to put this whole block in a subquery, please let me know
I don't think there's any such restriction. However, I suspect that your problem has to do with column aliasing. Here's what worked for me:
with totals as (select sum(column_name) c1 from some_table)
select c1 from totals;
Oracle might have complained because you were trying to do something like:
with totals as (select sum(column_name) from some_table)
select sum(column_name) from totals;
Unfortunately, this is a consequence of name resolution. The subquery's column will get named "sum(column_name)". Since sum is a function, there's no way to reference that column name without Oracle thinking you're referencing the function. You have to give it another name in order to reference it anywhere else.
Edit: It seems that you want to define a function as if you would a view subquery. I don't think anything like this is possible. View subqueries really only perform textual substitution.
PL/SQL functions require a whole different parser, name resolution, compilation process, etc. Having them work in queries alone is hard enough.
Sorry to say, but you'd have to define your packages/procedures/functions normally.
I need to be able to check a different table's value before allowing input in separate table.
In oracle they don't allow subqueries in check so I am trying to make a function...
CREATE OR REPLACE FUNCTION chktrain(tid integer)
RETURN INTEGER
AS
chk1 char;
BEGIN
SELECT chk1 = (select train from trainer where trainer.trainer_id = tid);
IF chk1 = 'Y' THEN
return 1;
ELSE
return 0;
END IF;
END;
This won't work because I can't set chk1 to the subquery. Is there a way to do this?
I believe you are looking for the SELECT INTO statement.
I'm not entirely sure you need to use this function you are creating though, but I'm also not sure I fully understand what you are trying to do. Perhaps look into triggers, specifically BEFORE INSERT triggers, which could allow you to lookup a reference table and potentially translate a value every time you do an insert on a table.
You are looking for SELECT INTO statement like
SELECT train into chk1 from trainer
where trainer_id = tid;
You might find this documentation interesting and helpful.
You will find railroad diagrams for the syntax of if statements and usage details about the different forms of if statements.
https://docs.oracle.com/cd/B19306_01/appdev.102/b14261/if_statement.htm
At the end of the page there is an example of the SELECT INTO statement.
(select train INTO chk1 from trainer where trainer.trainer_id = tid);
I have a problem which I can't solve. Maybe you have an idea about how to solve it.
I do have a given parameter-table like this:
P_VALUE P_NAME
----------- ----------
X85 A_03
XH1 A_04
XH2 A_04
XH3 A_04
C84 A_05
As you can see there are parameters with multiple entries. At the moment this parameters are used in this way:
SELECT * FROM tablex
WHERE code IN (SELECT p_value
FROM parameter_table
WHERE p_name LIKE 'A_04');
As the query is very big these parameter sub-select are used very often. I was trying to implement a function in Oracle to get my parameters. This works very fine as long as there is just 1 row per parameter. When I want to use it in "IN-Statements", it won't work because functions just return a single value.
--WORKS
SELECT * FROM tablex
WHERE code = (f_get_param('A_03'));
--DOES NOT WORK
SELECT * FROM tablex
WHERE code IN (f_get_param('A_04'));
Please note that I need it for plain SQL statements, so procedures won't work as they are just good for PL/SQL.
I would be really thankful for good ideas or help!
Use collections. Here you have an example http://www.adp-gmbh.ch/ora/plsql/coll/return_table.html
Technically you can achieve using the function this way but doing this will cause index not to be used on code column on tablex and may affect performance .Using function index you can reduce performance impact
CREATE OR REPLACE FUNCTION f_get_param(p_value1 IN VARCHAR2,p_name1 in VARCHAR2) return NUMBER
DETERMINISTIC
IS
l_count NUMBER;
BEGIN
select count(1) into l_count from parameter_table where p_value =p_value1
and p_name=p_name1;
if l_count > 0
then
return 1;
else
return 0;
end if;
end f_get_param;
AND use the select statement like this
SELECT * FROM tablex
WHERE f_get_param(code,'A_04')=1;
EDIT 1:-
Also to reduce the performance impact in database 10.2 and greater If the parameter_table is static you can use the DETERMINISTIC clause in the Function to say that the function returns the same value if called with same parameters every time
Please find the link on the article about using functions in SELECT statement
--DOES NOT WORK
SELECT * FROM tablex
WHERE code IN (f_get_param('A_04'));
-- Try this
SELECT * FROM tablex
WHERE code IN (select * from TABLE(f_get_param('A_04')));
You have to "CAST" a collection onto SQL TABLE.
Also when you use cast you can also use inner joint:
SELECT * FROM tablex join TABLE(f_get_param('A_04') using (code);
I think - generally - your problem is called "Dynamic where clause". Try to search some articles about it on AskTom.
I think the actual solution to your problem is to simply join the two tables and create the appropriate indexes rather than invoking a PL/SQL function at all:
SELECT x.* FROM tablex x, parameter_table p
WHERE x.code = p.p_value
AND p.p_name LIKE '%A_04%';
Note that you also have a semantic error in your LIKE clause. You're not using the % sign therefore your LIKE 'A_04' is just the same as = 'A_04'
As the title suggests, I would like to know if it is possible to join the string in a select statement within a PL/SQL procedure.
For example, I have something like this
SELECT FCS.CATEGORY,
FCS.NUMBERS,
FCS.POINTS
WHERE FCS.OBJECT = 'T'
AND FCS.THIS_DB & strSelectedDB &
So, is it possible to do something like this?
Your example is a little confusing. You can concatenate multiple strings using the || operator. But you'd then you'd have to compare the concatenated string to something. You can compare columns to local variables directly, though, i.e.
SELECT fcs.category,
fcs.numbers,
fcs.points
FROM some_table fcs
WHERE fcs.object = 'T'
AND fcs.this_db = strSelectedDB
assuming that strSelectedDB is a local variable in your PL/SQL block.